The New Zealand Plant Conservation Network

Species

Ranunculus acraeus

Etymology

Ranunculus: From the Latin 'rana' frog, meaning little frog and probably refers to the plants typical marshy habit where frogs abound

Common Name(s)

none known

Current Conservation Status

2012 - Threatened - Nationally Endangered

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - Threatened - Nationally Endangered
2004 - Not Threatened

Qualifiers

2012 - DP
2009 - DP

Authority

Ranunculus acraeus Heenan et P.J.Lockhart

Family

Ranunculaceae

Flora Category

Vascular - Native

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

None - first described December 2006.

Distribution

Endemic. South Island, North Otago (Barrier Range, St Marys Range, St Bathans Range, Kakanui Mountains and Ida Range) and in south-west Canterbury (Hall Range, Godley River valley).

Habitat

A high alpine species of stable, coarse rock-fields of greywacke and non-foliated schist.

Features

Robust, summer-green, rhizomatous herb, up to 40 cm high, forming patches up to 1 m across. Rhizomes numerous, stout, 10–12 mm diameter, regularly branched. Lamina 60–75 × 75–130 mm, broadly reniform or broadly orbicular, grey to grey-green, sparsely covered with pilose hairs, glabrate or glabrous, divided into 3 primary segments; margin crenate, teeth 2–9 mm long, broadly obovate, oblong to broadly oblong, apices obtuse, margin red; petiole 50–250 × 5–9 mm, fleshy, terete; sheath 15–40 mm, moderately to densely covered with pilose hairs. Inflorescence 80–400 × 5–14 mm, yellow-green to green, terete, with 1–6 flowers, each flower subtended by a leafy bract. Bracts similar to leaves, sessile, smaller toward distal flowers. Peduncles glabrous. Flowers 40–50 mm diameter. Sepals 6–7, 20–22 × 8–11 mm, yellow-green to light green, oblong, oblong-elliptic or broadly elliptic, hairy on abaxial surface, glabrous on adaxial surface. Petals 16–27, 22–27 × 5–13 mm, yellow, narrowly to broadly oblanceolate, apex obtuse, nectary a simple pit. Stamens 110–139, glabrous; filament 1.6–8.5 × 0.7–1.4 mm, translucent; anthers 1.8–2.8 mm long, cream. Carpels 126–171. Achenes 6.4–7.3 × 2.7–3.4 mm, yellow-brown; beak curved to ventral side, laterally compressed, tapering toward a point at apex.

Similar Taxa

Closest to R. piliferus (F.J.F.Fisher) Heenan et P.J.Lockhart from which it is can be distinguished by its finely crenate leaf and bract margins, glabrous peduncle; by the 6-7 abaxially hairy, adaxially glabrous sepals, and allopatric distribution.

Flowering

November - January

Flower Colours

Green,Yellow

Fruiting

December - January

Propagation Technique

Difficult. Should not be removed from the wild.

Threats

Uncommon. Known from c.200 plants on St Marys Range, 2 plants each on the Barrier Range and Hall Range, and an unknown number of plants at the other localities which are based on old herbarium specimens. At all recently visited sites plants are at risk from or are browsed by Thar and Chamois. Because it is a high alpine, and has been confused in past literature with other more common species, this species threat status is qualified as Data Poor (DP)

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 31 Jul 2014